Doc B,
First, let's go back to something Jar said. "Don't beat yourself up so much and try to just take it one day at a time". And, if the day is too much to handle just deal with the moment. There will be times when that is a handfull.
You said. "I began to get more alert and protective in public". That is a natural reaction based on the fact that you've seen just how dangerous and brutal this world can be. And, I'm not going to suggest that you ignore what you feel so deeply cause that's not gonna happen.
But, what I will suggest is you try hard to look at the reasons for you feelings. When you wake in the night with those old feelings take a look around. Check the house. It'll do a couple things. You'll be able to see that things are secure, and you'll burn off some of the chemicals your body produces when you in full alert mode.
Find help from those who know much more about this. Read "Once A Warrior, Always A Warrior". It's a great book written by someone whose been there. And, there are many others. Get to the VA and a Vet Center for professional help.
AND, KEEP TAKING THOSE BABY STEPS.
SD